Using default opt-out strategies to undercover the unknown HCV infections: a scoping review

Abstract Background Following the advent of directly acting antivirals (DAAs) a global effort is underway to eliminate viral hepatitis C (HCV) by 2030. Yet identification of infected individuals and access to dedicated services may pose a challenge to the achievement elimination targets. A scoping review to synthesize studies that explored the efficacy of opt-out strategies to improve HCV testing capacity was conducted. Methods We searched PubMed and Scopus (from 2015 to March 2022) for all English original articles and systematic reviews addressing opt-out strategies for HCV testing in different settings, published in the WHO's European Region Countries. We excluded articles that focused on other testing implementation strategies. Results A total of 136 articles were screened at the title and abstract level, of which 41 were also assessed at full text for eligibility after deduplication. In the end, 30 articles met the inclusion criteria. Studies originated from 19 different countries of the WHO's European Region, with the most prevalent being France (26.9%, 11/41). The 43.3% of the articles addressed opt-out testing strategies in emergency departments (EDs), 36.6% into prisons, 13.3% in primary care, and 6.6% among people who use drugs. Opt-out default testing was found to be effective in EDs and prisons, whereas only 2 articles tested the efficacy of opt-out strategies for HCV testing in primary care settings. Conclusions Opt-out strategies resulted in increased testing rates and higher cost-effectiveness in different settings, especially EDs and prisons. However, to identify individuals with undiagnosed infections, birth cohorts screening in the general population may be needed. Further research is needed to assess the utility of an opt-out default testing strategy in primary care settings. Key messages Opt-out strategies resulted in increased testing rates and higher cost-effectiveness in different settings. OpT-out strategies should be implemented in primary care settings to undercover the unknown infections.


Background:
The debate on vaccination strategies has been periodically involving researchers, policymakers, and also the population. Interest waves have occurred both after a revival of childhood infectious diseases in 2016-2017, due to low vaccine coverages, and during the recent Coronavirus outbreak. This study aimed at overviewing vaccination strategies (and corresponding vaccine coverages) for childhood vaccinations and SARS-CoV-2.

Methods:
Measles was chosen as a childhood vaccination indicator. Policy data were retrieved from health institutions (either European or national/regional) and, for COVID-19, also from press agencies and newspaper websites. Vaccine coverage data were retrieved from the World Bank, World Health Organisation, and UNICEF databases (for childhood vaccines), and from the ''Our World in Data'' platform for SARS-CoV-2. A qualitative comparison was performed between the two contexts. Results: Unlike childhood vaccinations, few countries (and only Austria in Europe) imposed generalised COVID-19 mandates, most countries preferring targeted mandates for higher-risk groups. Many countries confirmed their traditional voluntary vaccination approach also for COVID-19, while countries historically relying on compulsory vaccination strategies, such as Slovenia and Hungary, surprisingly opted for voluntary SARS-CoV-2 vaccination, with unsatisfactory results. However, no tangible crude association was generally found between vaccination policies and achieved coverages, although factors such as cultural background, education, and religion appeared to influence the impact of vaccination policies.

Conclusions:
The COVID-19 experience has enriched pre-existent vaccination strategy debates by adding interesting elements concerning attitudes toward vaccines in a novel context. Reading the available results in the frame of vaccine hesitancy determinants can help to understand the relationship between policies and actual coverages. Key messages: Few countries have imposed generalised mandates for COVID-19, while many preferred targeted obligations for high-risk groups and some countries surprisingly opted for a voluntary approach. Accurately considering social and cultural determinants allows understanding the chance of success of vaccination strategies, ahead of fostering the right policymaking approach for each population.
Abstract citation ID: ckac130.233 Using default opt-out strategies to undercover the unknown HCV infections: a scoping review We excluded articles that focused on other testing implementation strategies.

Results:
A total of 136 articles were screened at the title and abstract level, of which 41 were also assessed at full text for eligibility after deduplication. In the end, 30 articles met the inclusion criteria. Studies originated from 19 different countries of the WHO's European Region, with the most prevalent being France (26.9%, 11/41). The 43.3% of the articles addressed opt-out testing strategies in emergency departments (EDs), 36.6% into prisons, 13.3% in primary care, and 6.6% among people who use drugs. Opt-out default testing was found to be effective in EDs and prisons, whereas only 2 articles tested the efficacy of opt-out strategies for HCV testing in primary care settings.

Conclusions:
Opt-out strategies resulted in increased testing rates and higher cost-effectiveness in different settings, especially EDs and prisons. However, to identify individuals with undiagnosed infections, birth cohorts screening in the general population may be needed. Further research is needed to assess the utility of an opt-out default testing strategy in primary care settings. Key messages: Opt-out strategies resulted in increased testing rates and higher cost-effectiveness in different settings.
OpT-out strategies should be implemented in primary care settings to undercover the unknown infections.